(Probably) False. Chrono Trigger originated the terminology, but earlier games had features to replay the game.
However, do these earlier games let you keep equipment/levels/whatever, or do they just make the game harder?
This feels very likely to be false. Surely some earlier RPG had meaningfully-different multiple endings. Ultima maybe?
Atlus Co., Ltd. (1987). Digital Devil Story: Megami Tensei
[Nintendo Famicom]. Namco Limited.
Oliver, G. (2020). Renegade or Paragon? Categorizing Narrative Choice in Video Game Storylines. Dialogue: The Interdisciplinary Journal of Popular Culture and Pedagogy
Quest Corporation. (1993). Ogre Battle: The March of the Black Queen
[Nintendo Super Famicom]. Quest Corporation.
Square Co., Ltd. (1995). Chrono Trigger
[Nintendo Super Famicom]. Square Co., Ltd.